Comment 2 for bug 938549

StacktraceTop:
 g_assertion_message (domain=<optimized out>, file=<optimized out>, line=<optimized out>, func=0x7fea4328da40 "gsd_wacom_device_set_current_stylus", message=0x7fea5d616920 "assertion failed: (device->priv->styli)") at /build/buildd/glib2.0-2.31.18/./glib/gtestutils.c:1860
 g_assertion_message_expr (domain=0x7fea4328beea "wacom-cc-panel", file=0x7fea4328ccbb "gsd-wacom-device.c", line=1416, func=0x7fea4328da40 "gsd_wacom_device_set_current_stylus", expr=<optimized out>) at /build/buildd/glib2.0-2.31.18/./glib/gtestutils.c:1871
 gsd_wacom_device_set_current_stylus (device=0x7fea5d5a2e90, stylus_id=0) at gsd-wacom-device.c:1416
 setup_property_notify (device=0x7fea5d5a2e90) at gsd-wacom-device.c:411
 gsd_wacom_device_constructor (type=<optimized out>, n_construct_properties=<optimized out>, construct_properties=<optimized out>) at gsd-wacom-device.c:1167